"Degloving and Severe Upper Extremity Injuries in Motor Vehicle Crashes Involving Partial Ejection" Seattle CIREN University of Washington, Harborview Medical Center, Seattle WA Kaufman R., Blanar L., Bulger E. Seattle CIREN, UW, HMC Lipira A., Friedrickson J. Harborview Medical Center Mastrioanni S., Nelson M. Seattle CIREN
Upper Extremity (UE) Partial Ejection in Motor Vehicle Crashes (MVC) Noted as an arm or hand outwindow phenomenon Upper extremity partial ejection in MVCs can result in contact to exterior objects, including the ground in rollovers, which can result in severe degloving type injuries These severe injuries result in devastating and long lasting consequences J Trauma Acute Care Surg. 2013 Feb;74(2):687 91. Vehicle factors and outcomes associated with hand out window motor vehicle collisions. Bakker A 1, Moseley J, Friedrich J.
Partial Ejection Mitigation Seatbelts are 99.8% effective at preventing complete ejections, but only 38% effective in preventing partial ejections in rollover crashes Side curtain airbags (SABs) can reduced and mitigated risk of partial ejection BUT, most partial ejection research focuses on head or thoracic injuries Partial ejection of the upper extremity (UE) remains a highly morbid mechanism of upper extremity injury in motor vehicle collisions References: 1. Bakker, A., Moseley, J. & Friedrich, J. Vehicle factors and outcomes associated with hand out window motor vehicle collisions. Journal of Trauma and Acute Care Surgery 74, 687 691 (2013). 2. Ball, C. G., Rozycki, G. S. & Feliciano, D. V. Upper Extremity Amputations After Motor Vehicle Rollovers. The Journal of Trauma: Injury, Infection, and Critical Care 67, 410 412 (2009). 3. Nikitins, M. D., Ibrahim, S. & Cooter, R. D. Injury to arms protruding through vehicle windows. Hand Surg 8, 75 79 (2003). 4. Harris, C. N. & Wood, V. E. Rollover injuries of the upper extremity. The Journal of Trauma: Injury, Infection, and Critical Care 18, 605 607 (1978). 5. Funk, JR, Cormier JM, Bain CE, Wirth JL, Bonugli EB, Watson RA Factors affecting ejection risk in rollover crashes. AAAM 2012;56:203 11
Severe Upper Extremity Injury due to Partial Ejection Research has been limited to small studies from single centers No national level studies Research has generally been limited in evaluating injury and crash details of partial ejection. Research objectives: to evaluate severe UE injuries in relation to partial ejection examine role of side curtain bags in prevention of UE severe injuries (and in turn, evaluate overall partial ejection prevention).
Treatment of Severe Soft Tissue Degloving Injuries
Contents Definition Causes Classifications Treatments/Procedures Case Studies
Definition (Severe degloving soft tissue injury) Result of shearing force applied to skin surfaces Separation of skin and subcutaneous tissues from underlying muscle and fascia leads to the creation of a space allowing for accumulation of fluid Shearing forces disrupt and perforate vessels at the fascial level which may lead to skin necrosis(death) Frequently associated with fractures and other life and limb threatening injuries.
Mechanism of Severe Soft Tissue Injuries Injury occurs during ejection in a motor vehicle crash, or when a patient is thrown across a fixed surface Entrapment between a fixed surface and a moving object arm exiting vehicle contacting ground or trapped between vehicle exterior and ground
Classifications for Severe Soft Tissue Injury Pattern 1 Abrasion/Avulsion Loss of tissue as a result of abrasive force; little undermining of remaining skin edges Pattern 2 Non circumferential degloving Majority of skin is still present either as a flap or as an area of extensive undermining Pattern 3 Circumferential single plane Either open or closed confined to a single plane(between deep fascia, subcutaneous fat and skin) Pattern 4 Circumferential multi plane degloving Pattern # 3 plus breach of muscle groups or muscle and periosteum Arnez, Z.M. & Khan, U. (2010). Classification of soft tissue degloving in limb trauma. Journal of plastic and reconstructive surgery, 63,1865 1869.
Treatments and Procedures Conservative Subcutaneous hematoma and dead fat is removed followed by drainage and pressure dressings Injured muscle not directly inspected May hide compartment or crush syndrome Surgical Serial excisions prior to reconstruction Potential for bone desiccation and infection Negative Pressure Wound Therapy Wound VAC
Negative Pressure Wound Therapy Wound VAC Treatment of acute and chronic wounds Contaminated wounds, burns, infiltrations, envenomations, grafts, failed operations
Negative Pressure Wound Therapy Wound VAC Open degloving injuries Primary treatment Secondary treatment Temporary wound cover; Serve as a bridge to reconstruction; improves graft success
Length of Stay for Severe Soft Tissue injuries Required hospitalization for long periods Involved multiple and repeat surgeries Graft procedures fail, repeated In some severe cases an extremity may require amputation
Severe Soft Tissue Upper Extremity CIREN Case Studies
Case Study #1 45 year old male status post side impact of car versus light pole. Patient found to have right pneumothorax, pulseless right upper extremity with degloving injury to right shoulder, right 1 5 rib fractures, open right humerus fracture and radio/ulnar fractures Angiography revealed a right brachial artery transection versus a complete occlusion
Case Study #1 Scene
Case Study #1 Vehicle
Case Study #1 Injury Diagram Large lacerations and large avulsion/degloving of the shoulder /arm musculature with transection of the pectoralis major muscle, transection of the brachial artery leading to tissue ischemia Right Rib fractures 1 5 (with pnuemothorax) Open humerus shaft fracture Displaced Right radius and ulna fractures Case #
Operations/Procedures Day 1 OR #1 Part 1:Repair of right brachial artery with interposition bypass graft using reverse left greater saphenous vein Part 2: Open reduction and internal fixation of right both bone forearm fracture, irrigation and debridement(i&d) of open right forearm fracture Part 3: Open reduction and internal fixation of right humerus fracture Day 3 OR #2 I & D right humeral shaft fracture & right forearm fracture. Application of wound closure device, delayed primary closure
Operations/Procedures cont. Day 6 OR #3 I & D right humerus & right forearm, wound VAC change Day 8 OR #4 I & D right humerus & right forearm, wound VAC change Day 11 OR #5 I & D right humerus & right forearm, wound VAC change, Dressing change Day 15 OR #6 I & D right humerus & right forearm, application of wound VAC to right upper extremity from wrist to axilla Day 19 OR #7 I & D right humerus & right forearm, wound VAC change
Operations/Procedures Day 22 OR #8 I & D right humerus & right forearm, wound VAC change Day 25 OR #9 Ligation of previous right axillo brachial bypass graft secondary to blowout of graft and subsequent hemorrhage Day 26 OR #10 Open through elbow amputation Day 28 OR #11 I & D right upper extremity Day 30 OR #12 I & D right upper extremity including debridement, subcutaneous tissue, bone and muscle
Operations/Procedures cont. Day 32 OR # 13 Extend right elbow amputation to right shoulder disarticulation, excision of residual and infected bypass graft of the right arm, resection of chest wall wounds and rotation of large fasciocutaneous flap to the defect of the shoulder and chest wall Discharged on Day 37
ICU days: 1 Ventilation days: 1 LOS: 37 days Acute Healthcare only costs: $264,769.90 Does not include professional fees, radiology
Case Study #2 36 year old belted female who was involved in a low speed motor vehicle collision and rollover. Patient reported that she had her left arm out of the window when she was hit on the passenger side and rolled to the driver side. Patient found to have left ulnar styloid fracture and extensive left forearm/hand avulsion injury No other injuries
Case Study 2 Scene/Vehicle Case vehicle 2004 compact utility vehicle Far side & Rollover (2 quarter turn to left Objects struck V2 (2006 Chrysler Sebring) & the ground Daylight, Clear, Dry
Case Study 2 Occupant/Impact Driver Female 36yrs. 5 2, 220 lbs Normal posture Restraint Use = Manual lap/shoulder belt (seat belt retractor pretensioner did not actuate); no air bag deployments PDOF = Non Horizontal (Event #2) CDC 00LDEO01 Delta V Damage Severity = Minor
Arm partial ejection evidence
External Injury Left degloving injury of the forearm and hand Extensor tendon avulsion Left comminuted fracture of the distal ulna. Left thumb abrasion Case #
Operations/Procedures Day 2 OR #1 Irrigation and debridement(i&d) of left forearm avulsion injury including skin, subcutaneous tissue, muscle, and bone approximately 400 sq. cm. Exploration of median and ulnar nerves in forearm Day 5 OR #2 I & D left forearm with application of wound VAC Day 7 OR #3 I & D left forearm with wound VAC change Day 10 OR #4 Left forearm and dorsal hand debridement including skin, subcutaneous tissue, and muscle; wound VAC change
Operations/Procedures cont. Day 14 OR #5 I & D left dorsal forearm including skin & subcutaneous tissue; wound VAC change Day 21 OR #6 Preparation of wound bed for left dorsal forearm and hand, 400 sq. cm., in anticipation of a split thickness skin graft Application of split thickness(sheet) graft, 400 sq. cm., to left dorsal forearm and hand Day 24 Discharged
Case Study #2 ICU days: 0 Ventilation days: 0 LOS: 24 days Acute Healthcare only costs: $134,191.48 Does not include professional fees, radiology
Case Study # 3 22 year old restrained male driver who lost control of his car impacted a wall, and rolled. There was a prolonged extrication and he was noted to have his right arm trapped beneath the car and the ground out of the sunroof. He was found to have a right forearm degloving injury, 120 sq. cm., 20 cm. laceration, and right distal ulnar fracture
Case Study #3 Case vehicle 2005 (4 door sedan) Near side, Rollover on to roof Objects struck Concrete block wall & ground (rollover) Dark, rainy, wet roadways Male driver 22 yrs. 6 3, 220 lbs Seated height = 34 /86cms Manual lap/shoulder belt Airbag status = Side impact and curtain air bag deployments
Impacts VEHICLE #1 VEHICLE #2
Exterior
Contacts
External Injury Right forearm degloving injury and lacerations Right distal ulna fracture Case #
Operations/Procedures Day 1 OR #1 Irrigation and Debridement (I&D) of right forearm degloving injury including skin, subcutaneous tissue, and muscle Repair and closure of 20 cm laceration Removal of foreign bodies Open reduction and internal fixation of right ulnar fracture Day 5 OR #2 I & D of right forearm including skin, subcutaneous tissue, and muscle Delayed primary closure of 8 cm of laceration Day 12 OR # 3 I & D of right forearm, split thickness skin grafting, wound VAC application Discharged Day 16
Case Study # 3 ICU days: 0 Ventilation days: 0 LOS: 16 days Acute Healthcare only costs : $231,000.00 Does not include professional fees, radiology
Research Methods Data source: NASS CDS 1993 2012 (20 years) Passenger vehicles Outboard seats only (11, 13, 21, 23, 31, 33) Age 14 and above Three point belt used Sub analysis of side airbag deployment: 2000 2012 MY 2000 2012 Outboard seats only (11, 13, 21, 23, only) Three point belt, and not belted
Upper extremity definition Body region information is determined by the first digit of the AIS code (body region=7) Upper extremities injuries were included if AIS was greater than or equal to 2 along with finger amputations, joint dislocations and finger fractures (AIS 1).
For upper extremity (all injuries are AIS>2 unless otherwise specified: Severe soft tissue injury refers to: amputations (excluding fingers AIS 1), deglovings, crush injuries Moderate soft tissue injury refers to: skin lacerations, avulsions Functional structure injury refers to: artery and vein lacerations, nerve lacerations, muscle avulsions Shoulder joint injury refers to: shoulder joint subluxation (possible AIS 1), dislocation, acromioclavicular joint subluxation (possible AIS 1), dislocation, Upper arm fracture refers to: humerus fracture, unspecified arm fracture Elbow joint injury refers to: elbow joint dislocations (possible AIS 1) Forearm facture refers to: radius fracture, ulna fracture, forearm fracture Hand injury refers to: unspecified hand fracture, carpus fracture, metacarpus fracture, phalange fracture (AIS 1), carpal joint dislocation (possible AIS 1), and finger/thumb amputations Compartment syndrome: compartment syndrome to the arm, forearm, or hand Note that the following injuries are AIS >2 but are not included in the analysis of upper extremity injures: Clavicle fracture, Scapula fracture, Joint capsule injury, Sternoclavicular joint
Analysis Primarily descriptive statistics and chi squared test to determine differences between groups. To evaluate partial ejection prevention associated with side curtain airbag deployment, a logistic regression model was used First univariate Then adjusted for belt use, delta V Nearside and rollover
Population demographics Group N Rounded Annual Percent (%)* Mean N Total Population** 24,102,898 1,200,000 100 Belted 16,744,426 850,000 69.5 Driver 13,444,984 650,000 80.3 Front passenger 2,785,513 140,000 16.6 Other 513,929 25,705 3.0 Partially Ejected 235,341 12,000 0.98 Belted and Partially 102,123 5,000 0.59 Ejected Upper Extremity (UE) 918,466 46,000 3.81 Injuries Belted UE Injuries 520,649 26,000 3.11 Rollover 2,865,235 150,000 11.95 Average occurrences per year, 1993 2012 (N divided by 20) * Percent of total population (24,102,898) unless otherwise noted ** Outboard occupants, age 14 years or older Percent of all belted occupants (16,744,426)
Upper Extremity Injury Groups (Occupant level) All (N=24,102,898) Belted (N=16,744,426) UE Injury Group N % N % Severe soft tissue injury 16,736 0.070 8,175 0.049 Moderate soft tissue injury Compartment syndrome Functional structure injury 10744 0.040 8,731 0.052 44,962 0.190 30,266 0.180 9059 0.038 4,127 0.025 Shoulder joint injury 88,111 0.370 48,706 0.290 Upper arm fracture 196,539 0.820 86,141 0.510 Elbow joint injury 20,885 0.090 10,368 0.062 Forearm fracture 383,059 1.590 215,308 1.290 Hand injury 321,264 1.330 205,358 1.230
Occupant partial ejection and UE injury Total UE injury UE injury (%) No ejection 16,625,163 501,620 3.0 Partial ejection 102,123 16,547 16.0 Complete ejection 5334 986 18.5
Severe Soft Tissue Injury (SSTI) Breakdown, mechanism (belted) Contact with Ground or External Objects All* Partial Ejection** Amputation 29% 67% Crush Injury 57% 79% Degloving 44% 70% Injury All SSTIs 46% 73% SSTI = severe soft tissue injury *Percent of all injury type resulting from contact with ground or external objects **Percent of all injury type in partial ejection resulting from contact with ground or external objects
Partial ejection w/ specific UE injury types 100% 90% 80% 70% 60% 50% 40% 30% 20% partial complete no ejection 10% 0%
Occupant partial ejection (PE), belted, all crash types w/ UE injury by vehicle body type Total Partial Ejection (PE) PE with UE Injury %PE* % of PE with UE Injury** Passenger car 11,300,918 40,162 5359 0.35% 13.6% SUV 434,351 2,338 1376 0.54% 58.9% Minivan/vanbased 1,251,143 10,198 260 0.77% 2.6% light truck Pickup truck 1,809,937 25,856 3804 1.44% 14.7% Other light truck 14,205 506 0 3.62% 0.0% *Percent of group with partial ejection. Chi squared: P =0.0009 ** Percent of partially ejected occupants with UE injury
Partial ejections (belted occupants) by Primary Crash Type Principle crash type Total PE % PE* Front 9,376,921 13,293 0.14% Rear 1,609,512 10,507 0.69% Rollover 1,407,023 49,882 3.50% Nearside 1,836,783 22,447 1.22% Farside 1,416,343 3535 0.25% Total 15,646,582 99,804 0.64% *Percent of group with partial ejection. Chi squared: P <0.0001
Primary crash type in partial ejection with UE and SSTI injury Total UE injury % UE injury SSTI % SSTI % Deglove Injury Front 13214 3757 28.9% 1367 10.5% 4.8% Rear 10508 509 4.6% 110 1.0% 0.9% Rollover 49627 8627 17.6% 3046 6.2% 3.0% Nearside 21852 1852 8.4% 84 0.4% 0.2% Farside 3535 1053 29.8% 198 5.6% 2.9% Total 98,736 15,798 16.0% 4,805 4.9% 2.4%
Primary crash type in upper extremity injury groups in partial ejection 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% farside nearside rollover rear front
Ejection paths in UE injury Groups Severe soft tissue injury* (stat.signif) Windshield Left front Right front Left rear Right rear Rear Roof Other 173 2,278 664 43 268 0 1,412 0 UE injury 211 11,633 2,116 153 268 112 1,582 33
Partial ejection paths in rollover by quarter turns (Belted Drivers only) Quarter Turns 1 Right 1 Left 2 3 to 6 7+ Total Windshield 429 0 4 0 132 565 Left front 79 14,447 6944 15,211 4,926 41,160 Right front 51 0 23 23 1,631 1,728 Left rear 0 0 0 99 0 99 Right rear 0 0 0 0 145 145 Rear 0 0 0 0 33 33 Roof, Sunroof 0 0 2489 582 515 3,586 Total Partial Ejections in Rollover 559 14,447 9,460 15,915 7,382 47,316
Partial ejection paths among belted occupants in a rollover crash with at least 2 quarter turns (excludes complete ejection) no sunroof sunroof no ejection 1,134,823 321,981 windshield 374 0 left front 19,385 7,611 right front 8,867 1,163 left rear 376 105 right rear 447 30 rear 79 33 soft top/removable roof structure 1,462 0 Sunroof 0 2,335 Other 39 49
Ejection Prevention Side curtain airbags From Years 2000 to 2012 (MY 2000 2012): 15.1% of individuals were in vehicles equipped with side curtain airbags, however these airbags did not deploy 81.2% were in vehicles without side curtain airbags. 3.5% experienced a side curtain airbag deployment in primary force direction. 48.3% occurred in frontal crashes 28.3% in nearside crashes 11.67% in rear impacts 8.33% in rollovers 4.9% in far side impacts.
Side Curtain Airbag Deployment and Partial Ejection Near side Impact The unadjusted odds of partial ejection in a near side crash was 3.88 (95% CI 1.52, 9.89) times higher for individuals in vehicles without side curtain airbags compared to individuals in vehicles where the side curtain airbag deployed.
Side Curtain Airbag Deployment and Partial Ejection Near side Impact Near side multivariate model: The average difference in odds of partial ejection, as compared to no ejection, for those without side airbags available compared to vehicles with side curtain airbags available and deployed, adjusted for delta V and seatbelt use is 3.92 (95% CI 2.07, 7.40, p<0.001).
Side Curtain Airbags and Upper Extremity Injury Near side Impact The odds ratio associated with sustaining ANY upper extremity injury was not significant for near side crashes. However, for near side severe soft tissue injury for belted and unbelted (weighted): severe soft tissue injury airbag available and deployed no side airbag available no 57,295 446,943 yes 0 86
Side Curtain Airbag Deployment and Partial Ejection Rollover For rollover crashes, the average difference in odds of partial ejection, as compared to no ejection, for those without side airbags available compared to vehicles with side curtain airbags available and deployed, adjusted for seatbelt use, and number of quarter turns, the odds ratio was 1.74 (95% CI 1.10, 2.73, p=0.019).
Side Curtain Airbags and Upper Extremity Injury Rollover The odds ratio associated with sustaining ANY upper extremity injury was not significant for rollover crashes. However, for rollover severe soft tissue injury for belted and unbelted (weighted) severe soft tissue injury airbag available and deployed no side airbag available no 24,539 529,482 yes 32 2,673
Limitation slide Rollovers: did not assess FMVSS 226 where the side curtain will deploy in rollover collision For rollovers, multiple paths of ejection Although ejection status is known, NASS CDS does not allow information about the specific body part ejected and is not linked specifically to the ejection path Work around was to link severe deglove injury to source of injury (ground, exterior objects) to partial ejection Although the sample is large overall, because SSTIs are relatively rare, the count for degloving injury is relatively small
Conclusions Deployed side curtain airbags showed partial ejection prevention among both belted and unbelted individuals Side curtains airbags are effective in preventing severe soft tissue injury related to partial ejection in near side impact and rollover collisions Perfect prediction NO severe soft tissue injuries occurred in near side impacts for belted outboard occupants when side curtain airbags deployed.
Future tasks Further evaluate ejection prevention of pure rollover crashes with vehicles meeting FMVSS 226 CIREN data identifies contributing factors for injuries related to partial ejection for further evaluation CDS data could add additional data to link partial ejections with body regions and paths. UE degloving types injuries are costly Evaluate some cost benefit analysis when side curtain bags provided an ejection prevention CIREN data has acute cares costs to utilize with patients only incurring a severe or deglove UE injury
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